The field of the invention is horizontal scanning circuits for cathode ray tubes and particularly linearity correction circuits for horizontal scanning.
Because of non-linearity inherent in horizontal scanning circuits an uncorrected horizontal deflection circuit causes images displayed on the CRT to be expanded on the left side of the display. Inventive activity has been applied to this problem resulting in a number of patented resistor-capacitor (RC) circuits and inductor-capacitor (LC) circuits which are adequate to correct linearity at normal operating rates of conventional CRT scanning circuits.
Conventional circuits normally require a secondary transformer associated with the flyback transformer. The secondary transformer is normally connected to LC circuits of various configurations such that the LC circuit is series resonant to maximize the energy across a capacitor, the charge on which is used to correct linearity.
At much higher operating speeds additional considerations are required. The higher operating speed requires consideration of component values necessary to achieve linearity with an adequate control range. In addition, care must be taken that the coil used in the linearity circuit does not overheat because of the high speed operation.